1. Field of the Invention
The invention relates to a capsule for two or more components of a material which are to be mixed together. The material can be a dental material, for example an impression material, a temporary restoration material or a filler material.
2. Background
In the dental sector, that is to say the sector involving dentists and dental technicians, various capsules are known for intraoral administration of materials consisting of one component or of two or more components which are to be mixed together. There are so-called “compules”, liquid/powder capsules, and paste/paste capsules.
The compule is a capsule having a cannula, a single chamber containing a one-component material and opening at the front into the cannula, and a piston which sits in the chamber at the rear. Such compules can contain, for example, the universal filler material Filtek™ Supreme and the universal composite Filtek™ Z250 available from 3M ESPE. For use, they have to be inserted into an applicator 62 (shown in FIG. 69) which, for example, is available from 3M ESPE as Capsule dispenser under article number 5706 SD or from Centrix™. These known applicators 62 each have a body with a handgrip, a holder for receiving the compule in a removable manner, a plunger, and a drive mechanism for the plunger. When the capsule sits in the holder and the drive mechanism is actuated by closing the hand, said drive mechanism then pushes the plunger into the chamber from the rear, so that said plunger initially bears on the piston and pushes it farther forwards. By means of the advance movement of the piston, the material is dispensed from the chamber through the cannula. Such compule applicators 62 are very widely available on the market.
The liquid/powder capsules contain a liquid component and a powder component which have to be kept separate from one another until the time of use. Such liquid/powder capsules are, for example, available under the names Aplicap™ and Maxicap™ from 3M ESPE. These capsules contain, for example, the two components, to be mixed together, of filler materials such as, for example, the glass ionomer filler material Ketac™ Molar, or the light-cured glass ionomer filler material Photac™ Fil Quick, or the silver-reinforced glass ionomer filler material Ketac™ Silver Molar, or luting cements such as, for example, the self-adhesive universal composite luting cement RelyX™ Unicem or the adhesive composite luting cement Compolute™ or the glass ionomer luting cement Ketac™ Cem. These known capsules have a cannula, a large mixing chamber which contains the powder and opens at the front into the cannula, a piston which sits at the rear in the mixing chamber, and a foil pouch which contains the liquid and covers a hole in the shell or outer wall of the chamber. To use it, the capsule is first activated by applying pressure in a suitable way to the foil pouch, so that the latter tears over the hole and the liquid is forced into the mixing chamber. The mixing chamber is larger than the joint volume of the two components, so that these can be mixed together by vigorous agitation, for example using the capsule mixer devices RotoMix™ or CapMix™ from 3M ESPE. They then have to be inserted into a suitable applicator 62, which for example is obtainable under the name Aplicap™ Applier (shown in FIG. 70) or Maxicap™ Applier from 3M ESPE. These known applicators 62 each have a body with a handgrip, a holder for receiving the capsule in a removable manner, a plunger 63, and a drive mechanism for the plunger 63. When the capsule sits in the holder and the drive mechanism is actuated by closing the hand, said drive mechanism then pushes the plunger 63 into the mixing chamber from the rear, so that said plunger 63 initially bears on the piston and pushes it farther forwards. By means of the advance movement of the piston, the material is dispensed from the mixing chamber through the cannula. Such applicators 62 for liquid/powder capsules are likewise widely available on the market.
The paste/paste capsules contain two pasty components which have to be kept separate from one another until the time of use. Such a paste/paste capsule is known from WO 97/21394, which additionally discloses an applicator for this capsule. This known capsule has a cannula, a static mixer, which sits in the cannula, two cylindrical chambers lying alongside one another and opening at the front into the cannula, and two cylindrical pistons which sit displaceably in the rear of the chambers. The known applicator has a body with a handgrip, a holder for receiving the capsule in a removable manner, two elongate plungers lying alongside one another, and a drive mechanism for the two plungers which, when the capsule sits in the holder, advances these into the two chambers from the rear. The chambers contain the two pasty components which, upon actuation of the applicator drive mechanism, are pressed forwards out of the chambers and into the cannula by the two pistons which are pushed farther into the chambers by the two plungers. Upon further flow through the cannula, the two component strands are mixed together by means of the mixer and finally dispensed as a ready-mixed material from the front of the cannula.
The paste/paste capsule known from WO 97/21394 cannot be used with the known compule applicators 62 described above, nor with the above-described known applicators 62 for liquid/powder capsules, both of which forms are widely available on the market, because these each have only a single plunger 63, while the known paste/paste capsule has two pistons.